Pivot control mechanism

ABSTRACT

The pivot control mechanism that selectively controls the rotation of the pivot control shaft by an electric impulse from the solenoid, which locks the pawl into the ratchet, thereby permitting the shaft to rotate in a selected direction. 
     When a passage direction is chosen, the cam followers move out of the home position of the lofted ratchet over the peak position to the next home position. 
     The guiding pins controlling the axial motion of the lofted ratchet in conjunction with the compression springs secure the cam followers in the home position. 
     The shock absorber acting on the cam is used to prevent the turnstile from over rotating with any great amount of force, hence softening the return of the cam followers to the home position. 
     The micro switch is activated, sending a signal to the control board, which through the action of the solenoid, locks the pawls into the ratchet.

BACKGROUND OF THE INVENTION

This invention pertains to the pivot control mechanism used within the turnstile for the sole purpose or process of controlling passage between two separate areas.

In recent years, turnstile pivot control mechanisms have become increasingly more sophisticated in facilitating the monitoring of personnel passage between two separate areas.

Only recently, the pivot control mechanism has redeveloped from mechanical to electro-mechanical devices.

Typically, the pivot control mechanisms have been bulky and costly to construct. Such construction has suffered from a number of inherent problems. One problem would be the double ratchet operation, requiring multi-sets of hardware for each direction of motion, resulting in bulk and additional weight to the mechanism. A second problem would be if the operation were a clutched operated mechanism, requiring constant maintenance to keep the operation constant.

Additionally, a further problem has been the number of individual or separate components used in the manufacturing process of the pivot control mechanism owing to inventory, manufacturing and assembly difficulties.

These problems all contribute to the mechanism being excessively heavy, awkward to handle, costly to manufacture, ship and install.

Still another problem encountered with the mechanisms construction has centered on the rotor control mechanism. It is these mechanisms, which facilitates the rotational control of the rotor, accommodating the both directional operations. These in the past, have been a large component and take excessive space to accommodate.

The present invention contemplates a new and improved mechanism that overcomes all of the above indentified problems and provides a new pivot control mechanism construction, that is simple in design and economical to manufacture.

BRIEF SUMMARY OF THE INVENTION

In accordance with the new and improved pivot control mechanism construction, the pivot control mechanism facilitates selective rotational control of the pivot column through a plurality of operational modes. Traditionally it is contained in a “U” shaped channel, attached to the cage like structure by way of the bearing mounting holes that contain the main plate mounted directly on the channel by means of using the bearing flange mounting holes or by welded blocks on the bottom of the channel for improved security.

There are four studs on the main plate supporting the top plate. In between the main plate and the top plate is located the pivot control mechanism.

On the main plate are two flanges with a bearing, four plate studs to hold the top plate and four threaded rods connecting the middle plate. On the middle plate are three guided rods on which the lofted ratchet slides and three compression springs. The top plate has two arm micro-switches with rollers, a bearing, and a shock absorber mounting bracket with a shock absorber, a shock rod, a shock block and a cam follower. Additionally, attached to the top plate is a solenoid bracket with solenoid. Also contained are two locking pawls with torsion springs pivoting on shoulder screws with a thrust washer. A shaft is captured in a top plate bearing and main plate bearing with three shoulder screws with cam followers attached.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a Diametric View of the pivot control mechanism formed in accordance with the present invention.

FIG. 2 is an Oblique Top View of the pivot control mechanism with the top plate and solenoid removed.

FIG. 3 is a Top View of the pivot control mechanism with the top plate removed.

FIG. 3A is a detailed view of the pawl and ratchet.

FIG. 4 is a Plan View of the pivot control mechanism with the top plate removed.

FIG. 5 is a Reverse Plan View of the pivot control mechanism.

FIG. 6 is a Home Position view of the simplified pivot control mechanism.

FIG. 7 is a Peak Position view of the simplified pivot control mechanism.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the drawings, they only demonstrate the purpose of preferred embodiment of the invention and not for the purposes of limiting same. The figures illustrate a pivot control mechanism in seven detailed construction views. More specifically, FIG. 1 conventionally demonstrates the pivot control mechanism according to the present invention that includes a top plate 46, with a switch adjustable plate 15 on which an arm micro-switch with roller 14 is attached to the switch activator 27 and is held on the pivot control shaft 26 by a setscrew 50. Additionally connected to the top plate 46 is the shock absorber bracket 16, fastened with hex socket cap screws 51, and the adjustable shock absorber 17. Connected hereunder to the shaft 26 is a ratchet 29 and cam 30 made from one piece of metal as demonstrated in FIG. 2.

With reference to FIG. 5, thrust-bearing 28 absorbs the axial load of the compression springs 9 and transmits the load to the top plate 46.

The shaft 26 rotates in the top plate bearing 7 and the shaft bearing 4. The shaft bearing 4 is captured in the upper and lower flange 2 and 3 and is fastened to the main plate 1 with hex socket cap screws 48. The shaft 26 is held in the shaft bearing 4 with set of set-crews 47, FIG. 4.

Four plate studs 6 are screwed into the main plate 1, connects the top plate 46 with hex nuts 52.

The ratchet 29 with six equidistantly spaced grooves on the circumference, controls the direction of the rotation of the mechanism in conjunction with the pawl 24.

The rotatably mounted cam 30 has a continuous peripheral cam surface with a plurality of equidistantly spaced apexes attached to the pivot control mechanism shaft 26. The shock cam follower 19 rotates on shoulder screw 54 which is fastened to the shock rod 18, that sliding inside the slider body 20 on the bushing 35 (not illustrated) and is aligned in position with pin 34.

The shock cam follower 19 engages with the cam surface 30, providing general bias in association with the shaft 26. The lofted ratchet cam followers 31 run on the surface of the lofted ratchet 13 to the home position.

The shock absorber 17, FIG. 3 can be adjusted either by increasing or decreasing the force on the shock cam follower 19 which rotates on the shoulder screw 54. The adjustment of the shock absorber 17 is made by rotating the shock absorber nut 37 on the shock absorber bracket 16 or by the shock absorber adjustable control 38.

The pawls 24, FIG. 3 rotate on shoulder screws 39 opening and closing the pawl 24, allowing the ratchet 29 of the pivot control mechanism to rotate in either direction. The right hand 25 or left hand 44 torsion spring are always in tension forcing the pawls 24 inward or outward direction from the ratchet, depending on the configuration of the mechanism. For strictly mechanical operation of the pivot control mechanism, the right hand torsion spring 25 controls the selective rotation only in one direction. The left hand torsion spring 44 controls the selective rotation of the pivot control mechanism in the other direction.

The pawl 24 as illustrated in FIG. 3 has a 93° (obtuse) corner. FIG. 3A illustrates said pawl 24 sliding into the groove of the ratchet 29. The 93° corner, FIG. 3A, allows an easy engagement and/or dis-engagement of the pawl 24 with the ratchet 29.

The chosen configuration of the turnstile determines the shape of the lofted ratchet 13. If the chosen turnstile has three sets of arms, the hollow cylindrical shaped lofted ratchet 13 is divided equally into three home positions and three peak positions. If there is a requirement for four sets of arms, the hollow cylindrical lofted ratchet 13 is divided into four home and four peak positions. The above configuration will also determine the number of grooves on the ratchet 29. For example, for three sets of arms equals six grooves, for four sets of arms equals eight grooves. This also correlates to the shape change of the cam 30.

Yet another option would be the provision of a manual key lock feature (not illustrated) which would allow for the selective disabling of one of the solenoids 17 resulting in a selective rotation of the mechanism.

In accordance with an aspect of the invention, “home” means the cam followers 31 are being interposed in the lowest position of the wave of the lofted ratchet 13, as illustrated in FIG. 6. In accordance with another aspect of the invention, “peak” means the cam followers 31 are positioned on the highest positions of the wave of the lofted ratchet 13 and is illustrated in FIG. 7.

The main objective of the invention is to present the new pivot control mechanism for selective control of the turnstile rotor. Other benefits and advantages of the new pivot control mechanism will become apparent to those skilled in the art, upon reading and understanding this specification.

Depending on the location of the card reading device, not illustrated, positioned either in an unsecured area or secured area, a signal is received from the reading device and is processed by the control board, not illustrated, allowing or disallowing passage to occur. The board energizes the solenoid 22, held by the solenoid bracket 21, pulling the solenoid core 49 inward. The solenoid spring 23, held in the solenoid core 49 with the spring pin 45, pulling on the pawl spring screw 36 or 53 overcomes the force created by the right or left torsion spring 25 or 44 pulling the pawl 24 into the groove of the ratchet 29. The pawl rotates around the shoulder screw 39 and the pawl shoulder screw thrust washer 40 in FIG. 2.

At that moment, the second solenoid is de-energized. The right or left hand torsion spring 25 or 44 extracts the solenoid core 49 from the solenoid 22 and disengages the pawl 24 from the ratchet groove 29. The spring pins 33 stops the pawl 24 from over-rotating as illustrated in FIG. 5. This permits rotation of the mechanism in one direction only.

Following the passage function, the arm micro-switch with roller 14 is activated by the switch activator 27, transferring the signal back to the control board, energizing the second solenoid 22, which locks the pawl 24 into the ratchet groove 29.

When the shaft 26 rotates, the cam followers 31, which are secured to the shaft with shoulder screws 32, role on the wave of the lofted ratchet 13 to the home position. For one passage the cam followers 31 travel over the peak FIG. 7, back into the home position FIG. 6. The free end of the shaft 26 can be modified to meet any existing turnstile system.

The lofted ratchet 29 has guide pin bushings 12 (not illustrated), that are pressed into the holes of the lofted ratchet 29, in which the guiding pins 11 slide.

The compression springs 9, inserted over the spring pin 10, secured in the middle plate 8, keep constant pressure on the lofted ratchet 13, securing it in the home position. To keep the compression spring 9 constantly in contact with the lofted ratchet 13, the middle plate height 8 can be adjusted with nuts 42 on the threaded rod 5. When the desired pressure is set, the middle plate is secured with nuts 43.

The threaded rods 5 are locked in position on the main plate 1 with hex nuts 41. The rotation of the shaft 26 also generates pressure on the shock absorber 17 through the cam 30 attached to the shaft. This operation will smoothen the return of the cam follower 31 to the home position on the wave of the lofted ratchet 13. 

1. A pivot control mechanism construction adapted to electronically facilitate the selective passage between two defined areas, said pivot control mechanism comprising of a cam having a continuous cam surface with a plurality of apexes disposed at spaced intervals therealong.
 2. The pivot control mechanism locking member comprising of a rigid pawl having an obtuse angle, this said pawl also includes a means for cooperating with a suitable associated tool in order to allow said pawl to be rotated.
 3. The pivot control mechanism of claim 2 further comprising of a ratchet having grooves with an obtuse angle for easy engagement or disengagement of the pawl and for locking the pivot control mechanism in its home position.
 4. The pivot control mechanism further comprising of a lofted ratchet of a cylindrical shape and a having a continuous wave surface with a plurality of home and peak interval therealong and cam followers normally urged into the engagement with said wave surface for general biasing said pivot control mechanism to said home position and a locking means for selectively locking the pivot control mechanism to prevent rotation thereof.
 5. The pivot control mechanism further comprising of a middle plate engagement of the lofted ratchet for further pressure adjustment on the said lofted ratchet.
 6. The pivot control mechanism further comprising of guiding rods thereby controlling the axial motion of the lofted ratchet.
 7. The pivot control mechanism further comprising of compression springs acting on the lofted ratchet thereby securing said mechanism in the home position.
 8. The pivot control mechanism further comprising of a cam and ratchet having been made from of one piece of material.
 9. The pivot control mechanism further comprising of the pin inside the slider body which keeps the shock cam follower on the shock rod in full contact with the cam surface.
 10. The pivot control mechanism further comprising of a shaft with shoulder screws securing cam followers equidistantly on the circumference
 11. The pivot control mechanism construction is adaptable to any existing turnstile structure due to its size and configuration 